Two patients with myocardial bridging of the left anterior descending coronary artery associated with myocardial infarction are described. One of them died from acute cerebral emboli related to cardiac thrombosis in a left ventricular aneurysm. The other died suddenly while sleeping. Both patients were found to have a very long myocardial bridging of the left anterior descending coronary artery as well as patches of fibrosis in the left anterior descending coronary artery territory. Marked left ventricular hypertrophy was also found in the patient who died suddenly. No other cardiac abnormality was observed in either patient. These cases, together with those previously reported, suggest that myocardial bridging of the left anterior descending coronary artery can no longer be considered a benign coronary anomaly.